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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Study of the formulation optimization and reusability of a MAGAT gel dosimeter

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Autor(es):
Resende, Thiago Dias [1] ; Lizar, Jessica Caroline [1] ; dos Santos, Fred Muller [1] ; Borges, Leandro Federiche [2] ; Pavoni, Juliana Fernandes [2, 1]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Fac Philosophy Sci & Letters Ribeirao Preto, Phys Dept, Av Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil
[2] Univ Sao Paulo, Clin Hosp, Radiotherapy Serv, Med Sch Ribeirao Preto, Av Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: PHYSICA MEDICA-EUROPEAN JOURNAL OF MEDICAL PHYSICS; v. 63, p. 105-111, JUL 2019.
Citações Web of Science: 0
Resumo

Purpose: This study aims to optimize the formulation of a methacrylic acid gelatine and tetrakis (hydroxymethyl) phosphonium chloride (MAGAT) gel dosimeter to achieve acceptable dosimetric characteristics and the lowest final costs. This study also evaluates the reusability of the dosimeter. Methods: The MAGAT gel dosimeter formulation was optimized. Tetrakis (hydroxymethyl) phosphonium chloride (THPC) concentrations (2, 5, 8, 10, 20, and 65 mM), methacrylic acid (MA) concentrations (2.0, 2.5, 3.0, 3.5, and 4.0% w/w) and gelatin concentrations (4.36, 6.45, 8.36, and 10.45% w/w) were evaluated to provide an adequate dosimetric response. The final dosimeter formulation linearity and dose rate dependence were evaluated. The reutilization methodology of the optimized gel formulation, but containing 2 mM of THPC, which was previously irradiated with a dose of 2 Gy, is also presented. Results: The optimized mass concentration of the dosimeter consists of 88.60% deionized water, 8.36% gelatin, 3.00% of MA and 0.04% THPC (5 mM). It presents a linear response for doses up to 10 Gy with a 1.16 Gy(-1) s(-1) sensitivity. A maximum sensitivity variation of less than 4.0% was found when varying the dose rate of the radiation beams from 300 to 500 cGy/min. It was possible to reuse the dosimeter, however the sensitivity decreased by 15% from the first to the second irradiation. Conclusions: A low-cost MAGAT gel dosimeter with optimized formulation that responds to radiation in a dose range of 0 to 10 Gy with small dose-rate dependence is presented. The MAGAT gel can be reused after a 2 Gy irradiation. (AU)

Processo FAPESP: 14/03370-6 - Aplicações clínicas e otimização da técnica de dosimetria tridimensional com géis poliméricos
Beneficiário:Juliana Fernandes Pavoni
Linha de fomento: Auxílio à Pesquisa - Regular